Cedar Hill is an unincorporated community and census-designated place (CDP) in northwest Jefferson County, Missouri, United States.

[5] The community was named for cedar trees near the elevated town site.

[6] Cedar Hill is located 32 miles (51 km) southwest of downtown St. Louis.

Missouri Route 30, a four-lane highway, runs through the western side of the CDP, leading northeast into St. Louis and west 22 miles (35 km) to St. Clair.

According to the United States Census Bureau, the CDP has a total area of 2.3 square miles (5.9 km2), all land.